Low cycle Fatigue

[fruton]

Hello all,

I am looking at some low cycle fatigue tests and wondering if from a material study perspective. Is low cycle fatigue assessments normally conducted for overall material components or can it just be applied to micro surface cracks also?

Thanks

 

[metengr]

In simple terms, for low cycle fatigue you are dealing with fatigue crack propagation because the majority of the component's fatigue life is consumed under fatigue crack propagation from existing or inherent defects in the material.

High cycle fatigue deals primiarly with fatigue crack initiation, and fatigue crack propagation is a much smaller percentage of the component's fatigue life. Micro-crack initiation and subsequent crack propagation would be more applicable to high cycle fatigue studies.